1. Field of the Invention
The present invention relates to a surface-type fastener having a thick foundation fabric and stable in shape and configuration.
2. Description of the Prior Art
Conventional surface-type fasteners produced by weaving or knitting generally have a foundation fabric which is woven or knitted as thin as possible within an allowable range of strength in view of the required flexibility. The woven or knitted foundation fabric is then coated on its back surface with a synthetic resin such as polyurethane, so that the base portion of a number of raised interlocking elements composed of piles or hooks on the front surface of the foundation fabric is firmly secured to the foundation fabric. In the case where the conventional surface-type fastener is used as a binding strip, a backing material, such as a woven fabric, a knitted fabric, a leather or a non-woven fabric, is temporarily attached or tacked to the back surface of the foundation fabric either by adhesive bonding using an adhesive or a pressure sensitive adhesive double-coated tape, or alternatively by fusion bonding. The foundation fabric and the backing material are subsequently united together by sewing so as to provide desired thickness and stiffness.
The foregoing manner of unification, which is achieved by first tacking with an adhesive, for example, and then sewing the conventional surface-type fastener and the backing material, requires a plurality of manufacturing processes and hence lowers the productivity. Furthermore, due to the necessity of providing various backing materials which are well matched with the dimensions and colors of different conventional surface-type fasteners, the stock or inventory management is rendered extremely complicated.
Moreover, the aforesaid adhesive bonding using an adhesive or a pressure sensitive adhesive double-coated tape, or the fusion bonding is no more than tacking. Accordingly, the tacked portion may be separated during use of the binding strip, thus causing the surface-type fastener to separate from the backing material along its portion other than those sewn to the backing material. The surface-type fastener eventually becomes floating on the backing material along a portion defined between two adjacent lines of sewing stitches.